Something big happened along Florida’s storied Space Coast, and seismologists are currently clueless about what it may have been. On the evening of Friday, March 8, homes throughout east Central Florida were shaken by a powerful tremor around 10:45 pm local time. Residents reported doors shaking or walls vibrating for minutes, but luckily no severe damage or injuries were reported by what seismographs in the town of Century, Florida recorded as a 2.6 magnitude earthquake.

Florida is one of the least seismically active states, so geologists and seismologists aren’t exactly sure if the tremor was an earthquake per se. Some meteorological events can cause the ground to shake, and there are plenty of man-made phenomena which can rattle the ground forcefully enough to be recorded by seismographs; hundreds of such events have been recorded over the past few years. Is this event related to the mystery boom phenomenon I’m currently obsessed with?

It’s possible, especially given that due to the area’s proximity to space launch facilities and Air Force installations, many Florida residents suspected the tremor could have been caused by aerospace activity. “It could be something like a hypersonic jet, munitions…or a sonic boom,” says Paul Earle, a seismologist with the USGS. “Unfortunately, we can’t give a definitive answer on exactly what it was.”

Naturally, a spokesperson for Patrick Air Force Base gave a statement claiming there were no military air exercises that day which could have caused the tremor:

We’ve been informed that there have been reports of a rumbling noise in the Space Coast area this past Friday. Having checked with our local organizations within the 45th Space Wing, it does not appear to have come from us. So I cannot comment at this time as to its origin.

With little other information to go on, this mysterious tremor will be thrown on the already massive and still growing pile of evidence suggesting a mysterious natural or unnatural phenomenon is shaking the Earth throughout the United States. Will we ever know what’s behind these unexplained booms and tremors?